URLs no se resuelven cuando en Control de Usuario (ASP.NET)

Question

Si paso la testA una clase derivada PlaceHolder que contiene una Hyperlink, con una dirección URL que empieza una tilde, se resuelve correctamente. Sin embargo, cuando paso testB (Idéntico aparte de que hereda de System.Web.UI.UserControl) el mismo PlaceHolder Se lo vuelve literalmente (no lo hace transformar / resolver el '~')

¿Alguna idea?

public class testA : System.Web.UI.Control
{
    public System.Web.UI.WebControls.PlaceHolder plc { get; set; }
    protected override void OnLoad(EventArgs e)
    {
        if (plc != null)
            this.Controls.Add(plc);
        base.OnLoad(e);
    }
}


public class testB : System.Web.UI.UserControl
{
    public System.Web.UI.WebControls.PlaceHolder plc { get; set; }
    protected override void OnLoad(EventArgs e)
    {
        if (plc != null)
            this.Controls.Add(plc);
        base.OnLoad(e);
    }
}

Este es ASP.NET

Answer 1

When you inherit from System.Web.UI.UserControl and do not associate your control with an ascx file then your control TemplateSourceVirtualDirectory will not be set, this is required by the ResolveClientUrl method - if its null or empty the url will be returned AS IS.

To solve your problem, just set AppRelativeTemplateSourceDirectory :

public class testB : System.Web.UI.UserControl
{
    public System.Web.UI.WebControls.PlaceHolder plc { get; set; }
    protected override void OnLoad(EventArgs e)
    {
        if (plc != null)
        {
            this.AppRelativeTemplateSourceDirectory =
                    plc.AppRelativeTemplateSourceDirectory;
            this.Controls.Add(plc);
        }
        base.OnLoad(e);
    }
}

Answer 2

A UserControl is normally associated with an ascx file that defines its markup. Such controls should be instantiated using TemplateControl.LoadControl() before they're added to the page, in order to perform event catch-up.

I suspect that event catch-up does not take place since you don't call LoadControl(), so the Hyperlink's NavigateUrl never gets a chance to be properly resolved.